[....] Starting enhanced syslogd: rsyslogd[ 13.287960] audit: type=1400 audit(1517510407.506:4): avc: denied { syslog } for pid=3913 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 [?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.15.225' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 26.401796] ================================================================== [ 26.409197] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 26.416273] Read of size 8 at addr ffff8801c2cf1140 by task syzkaller053052/4069 [ 26.423773] [ 26.425372] CPU: 1 PID: 4069 Comm: syzkaller053052 Not tainted 4.9.79-g71f1469 #25 [ 26.433046] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.442370] ffff8801d3a379b0 ffffffff81d94829 ffffea00070b3c40 ffff8801c2cf1140 [ 26.450342] 0000000000000000 ffff8801c2cf1140 ffff8801d3fa0238 ffff8801d3a379e8 [ 26.458306] ffffffff8153e083 ffff8801c2cf1140 0000000000000008 0000000000000000 [ 26.466289] Call Trace: [ 26.468849] [] dump_stack+0xc1/0x128 [ 26.474190] [] print_address_description+0x73/0x280 [ 26.480832] [] kasan_report+0x275/0x360 [ 26.486428] [] ? sg_remove_request+0x103/0x120 [ 26.492640] [] __asan_report_load8_noabort+0x14/0x20 [ 26.499363] [] sg_remove_request+0x103/0x120 [ 26.505389] [] sg_finish_rem_req+0x295/0x340 [ 26.511416] [] sg_read+0xa16/0x1440 [ 26.516664] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.523297] [] ? fsnotify+0xf30/0xf30 [ 26.528718] [] ? avc_policy_seqno+0x9/0x20 [ 26.534574] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 26.541559] [] ? security_file_permission+0x89/0x1e0 [ 26.548284] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.554926] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.561562] [] do_readv_writev+0x520/0x750 [ 26.567416] [] ? vfs_write+0x530/0x530 [ 26.572933] [] ? __raw_spin_lock_init+0x1c/0x100 [ 26.579321] [] ? fasync_insert_entry+0x147/0x2e0 [ 26.585698] [] vfs_readv+0x84/0xc0 [ 26.590859] [] do_readv+0xe6/0x250 [ 26.596018] [] ? vfs_readv+0xc0/0xc0 [ 26.601354] [] ? entry_SYSCALL_64_fastpath+0x5/0xe8 [ 26.607995] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.614803] [] SyS_readv+0x27/0x30 [ 26.619962] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 26.626505] [ 26.628102] Allocated by task 0: [ 26.631433] (stack is not available) [ 26.635108] [ 26.636704] Freed by task 0: [ 26.639687] (stack is not available) [ 26.643364] [ 26.644959] The buggy address belongs to the object at ffff8801c2cf1100 [ 26.644959] which belongs to the cache fasync_cache of size 96 [ 26.657581] The buggy address is located 64 bytes inside of [ 26.657581] 96-byte region [ffff8801c2cf1100, ffff8801c2cf1160) [ 26.669245] The buggy address belongs to the page: [ 26.674144] page:ffffea00070b3c40 count:1 mapcount:0 mapping: (null) index:0x0 [ 26.682367] flags: 0x8000000000000080(slab) [ 26.686654] page dumped because: kasan: bad access detected [ 26.692332] [ 26.693934] Memory state around the buggy address: [ 26.698833] ffff8801c2cf1000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 26.706159] ffff8801c2cf1080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.713486] >ffff8801c2cf1100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.720811] ^ [ 26.726231] ffff8801c2cf1180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.733557] ffff8801c2cf1200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.740885] ================================================================== [ 26.748221] Disabling lock debugging due to kernel taint [ 26.753954] Kernel panic - not syncing: panic_on_warn set ... [ 26.753954] [ 26.761313] CPU: 1 PID: 4069 Comm: syzkaller053052 Tainted: G B 4.9.79-g71f1469 #25 [ 26.770206] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.779544] ffff8801d3a37908 ffffffff81d94829 ffffffff8419709f ffff8801d3a379e0 [ 26.787515] 0000000000000000 ffff8801c2cf1140 ffff8801d3fa0238 ffff8801d3a379d0 [ 26.795486] ffffffff8142f531 0000000041b58ab3 ffffffff8418ab10 ffffffff8142f375 [ 26.803453] Call Trace: [ 26.806016] [] dump_stack+0xc1/0x128 [ 26.811352] [] panic+0x1bc/0x3a8 [ 26.816337] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 26.824541] [] ? preempt_schedule+0x25/0x30 [ 26.830485] [] ? ___preempt_schedule+0x16/0x18 [ 26.836688] [] kasan_end_report+0x50/0x50 [ 26.842454] [] kasan_report+0x167/0x360 [ 26.848899] [] ? sg_remove_request+0x103/0x120 [ 26.855101] [] __asan_report_load8_noabort+0x14/0x20 [ 26.861826] [] sg_remove_request+0x103/0x120 [ 26.867857] [] sg_finish_rem_req+0x295/0x340 [ 26.873883] [] sg_read+0xa16/0x1440 [ 26.879128] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.885765] [] ? fsnotify+0xf30/0xf30 [ 26.891196] [] ? avc_policy_seqno+0x9/0x20 [ 26.897053] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 26.904034] [] ? security_file_permission+0x89/0x1e0 [ 26.910758] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.917396] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.924045] [] do_readv_writev+0x520/0x750 [ 26.929898] [] ? vfs_write+0x530/0x530 [ 26.935408] [] ? __raw_spin_lock_init+0x1c/0x100 [ 26.941786] [] ? fasync_insert_entry+0x147/0x2e0 [ 26.948160] [] vfs_readv+0x84/0xc0 [ 26.953318] [] do_readv+0xe6/0x250 [ 26.958479] [] ? vfs_readv+0xc0/0xc0 [ 26.963817] [] ? entry_SYSCALL_64_fastpath+0x5/0xe8 [ 26.970456] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.977267] [] SyS_readv+0x27/0x30 [ 26.982428] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 26.989485] Dumping ftrace buffer: [ 26.993004] (ftrace buffer empty) [ 26.996686] Kernel Offset: disabled [ 27.000284] Rebooting in 86400 seconds..